Display screen or portion thereof with transitional graphical user interface



FIG. 1 is a front view of a first image in a sequence for a display screen or portion thereof with transitional graphical user interface, showing our new design;

FIG. 2 is a front view of a second image thereof;

FIG. 3 is a front view of a third image thereof;

FIG. 4 is a front view of a fourth image thereof;

FIG. 5 is a front view of a fifth image thereof;

FIG. 6 is a front view of a sixth image thereof; and,

FIG. 7 is a front view of the graphical user interface of FIG. 1 shown separately in an exemplary environment comprising a mobile terminal, for clarity of illustration.

The appearance of the transitional image sequentially transitions between the images shown in FIGS. 1 through 6. The subject matter of this patent includes a process or period in which an image changes into another image. This process or period forms no part of the claimed design.

The mobile terminal and the text/words, numbers, symbols and otherwise images shown in broken lines in the drawing figures illustrate unclaimed subject matter. 

CLAIM The ornamental design for a display screen or portion thereof with transitional graphical user interface, as shown and described. 